A combination of physiological, anatomical, molecular and genetic approaches are used to elucidate basic neurobiological processes underlying mammalian parental care. Specific projects examine the involvement of the endocrine and nervous systems in the regulation of onset and maintenance maternal behavior. Studies using the rat as an animal model are delineating the role of the neural prolactin-like system in the onset of maternal behavior as well as role of specific brain structures in the hypothalamus. Project objectives include understanding the neurobiology of affiliative responses and disorders, such as post-partum depression.